BEKA BA374C, Руководство пользователя

Страница: 15 / 27

6.5.2 Low input & display calibration 'In-LO'
This function defines the lower voltage input and
the corresponding transmitter display. See
example below:
Input Transmitter
mV Display
-10.00 -3.000 Low input / display
12.55 3.765 High input / display
The calibration is performed using the internal
references and may be made with any transmitter
input voltage.
Select 'In-LO' from the menu and press P which
will access a sub-menu containing two functions
'InPut' and ''dISP'.
Select the input voltage 'InPut' and press P which
will cause the specified lower input millivoltage to
be displayed in the form XX.XX The flashing digit
of the input voltage can be changed by pressing
the
Up or Down buttons. When the first digit is
correct, pressing P will transfer control to the next
digit. When the least significant digit has been
adjusted, press
E to return to the 'InPut' prompt,
from which the display prompt 'dISP' can be
selected by pressing the
Up or Down button.
Pressing P will reveal the transmitter display
corresponding to the specified low input voltage.
The position of the dummy decimal point will be as
defined by function 'd.P.' - see section 6.5.1
The flashing digit of the display can be changed by
pressing the
Up or Down buttons. When the first
digit is correct, pressing P will transfer control to
the next digit. When the least significant digit has
been adjusted, press
E to return to the ''dISP'
prompt.
6.5.3 High input & display calibration 'In-HI'
This function defines the higher voltage input and
the corresponding transmitter display. See
example below:
Input Transmitter
mV Display
-10.00 -3.000 Low input / display
12.55 3.765 High input / display
The calibration is performed using the internal
references and may be made with any transmitter
input voltage.
Select 'In-HI' from the menu and press P which will
access a sub-menu containing two functions 'InPut'
and ''dISP'.
Select the input voltage 'InPut' and press P which
will cause the specified higher input millivoltage to
be displayed in the form XX.XX The flashing digit
of the input voltage can be changed by pressing
the
Up or Down buttons. When the first digit is
correct, pressing P will transfer control to the next
digit. When the least significant digit has been
adjusted, press
E to return to the 'InPut' prompt,
from which the display prompt 'dISP' can be
selected by pressing the
Up or Down button.
Pressing P will reveal the transmitter display
corresponding to the specified higher input voltage.
The position of the dummy decimal point will be as
defined by function 'd.P.' - see section 6.5.1
The flashing digit of the display can be changed by
pressing the
Up or Down buttons. When the first
digit is correct, pressing P will transfer control to
the next digit. When the least significant digit has
been adjusted, press
E to return to the ''dISP'
prompt.
6.6 4/20mA output current calibration 'CAL'
This sub-menu defines the relationship between
the transmitter display and the 4/20mA output
current. The transmitter output current is derived
from the transmitter display and will change if the
display calibration is changed. 'ZEro' defines the
display at which the output is 4mA, and 'SPAn' the
display at which the output is 20mA.
To calibrate the output current select 'CAL' from
the programme menu and press
P which will
access a sub-menu containing two functions.
Select 'ZEro' and press
P which will show the
transmitter display at which the output current is
4mA. The flashing digit of the display can be
changed by pressing the
Up or Down buttons.
When the first digit is correct, pressing P will
transfer control to the next digit. When the least
significant digit has been adjusted, press
E to
return to the 'ZEro' prompt, from which the span
prompt 'SPAn' can be selected by pressing the
Up
or Down button.
Press P to show the transmitter display at which
the output current is 20mA. The flashing digit of
the display can be changed by pressing the
Up or
Down buttons. When the first digit is correct,
pressing P will transfer control to the next digit.
When the least significant digit has been adjusted,
press
E to return to the 'SPAn' prompt.
Note: If a complete loop including a primary
element, BA374C temperature transmitter and a
load are being calibrated, the Trim Menu is the
preferred method. It allows the transmitter display
and output current to be adjusted to compensate
for inaccuracies in the other components in the
loop. Details of the trim menu are contained in
section 7 which also describes periodic calibration.
15